Process of making extracts from the redwood-tree



' UNITED STATES ATENT FFICjE.

ANDREW TAYLOR, OF EDINBURGH, SCOTLAND, ASSIGNOR TO CHARLES A. HOOPER, OF SAN FRANCISCO, CALIFORNIA.

PROCESS OF MAKING EXTRACTS FROM THE REDWOOD-TREE.

SPECIFICATION forming part of Letters Patent No. 509,703, dated November 28, 1893.

Application filed December 30. 1891. Serial No. 416,592. (Specimena) Patented in England June 18, 1887, No. 8,816.

To an whom it may concern.-

Be it known that I, ANDREW TAYLOR, a subject of the Queen of Great Britain, residing at Edinburgh, county 0: Mid-Lothian, Scotland, have invented an Improvement in Obtaining Vegetable Products from Redwood, (which said invention I have patented in England June 18, 1887, No. 8,816,) and I hereby declare the following to be a full, clear, and exact description of the same.

My invention relates to the art and process of obtaining vegetable products from the bark and wood of trees.

It consists in the processes hereinafter fully described and specifically pointed out in the claim of treating the bark or wood of the redwood tree (Sequoia sempervirens) to obtain a certain product or products, the nature and uses of which will be fully explained.

Heretofore the bark of the Californian redwood tree (Sequoiasempcrm'rcns) which is of exceptional length and thickness, has been virtually a waste product and of little known industrial value. is at present of a comparatively small value as a furniture wood, because it has been found to flake off when orking under the carpenters tools, and to warp to such an. extent in furniture made from it as to render it unsuitable for the purpose.

The ultimate result of my invention is to render the bark a useful article and the wood a more valuable one. To this end experiments were made with thebark and wood resulting in the discovery that the bark can be turned to usefulaccount, inasmuch as I found it contained tannins, gallates, kinos and other vegetable extracts, which could be extracted and used as commercial products. The wood was also found to contain like extracts.

I find that the preferable way of treating the bark and wood for obtaining the above named products is as follows: The bark or wood is cut into pieces of convenient size, ac-

cording to the subsequent purposes of use.

If extracts alone are desired to be manufactured, the pieces cut, as above specified, are

The wood of the tree also ground in a suitable apparatus, such as a disintegrator or tanners mill, to a powder, so that all the available extract may be obtained. But, when only a portion of the extract in a piece of bark or wood is required, it need not be cut into such small pieces. The bark or wood, treated in either of the above ways, is next steeped in water, preferably in vats or pans heated so as to produce a temperature of between 80 and 212 Fahrenheit. I prefer a temperature just below 212 Fahrenheit. To the above has been added caustic soda, soda crystals, or equivalent salts of potasl1,just as I want difierent shades of color in the extract. The more powerful alkali gives a brown color and thoroughly cleans the fiber; while, if ma terial for use in the more delicate wood stains or in dyeing, is required, Iprefer to use sodic carbonate or soda crystals, which give the liquid a light red color. In the latter case I prefer to use the proportion of seven pounds of crystals to thirty-iive pounds of ground powder, or so, in, say, forty gallons of water. The first batch, after boiling eight hours or so, will stand at 4 Twaddle; it is next filtered and allowed to cool, and stand over for a time so that impurities may settle to the bottom of the cooling tank. The clarified liquid is next boiled down at a similar temperature to 18 Twaddle, when it is a merchantable article.

Its uses are as follows:-The liquor from the bark gives a special redwood stain like the color of the wood. This may be modified by the woodstainer into a light or dark red, or a mahogany or satinwood, and a walnut stain or into a pine color. I find that the stain from the sequoia wood gives a color similar to the latter. The stain has been laid on the roughest and cheapest woods without previous preparation. It is thus adapted for cheap furniture making. It can also be used for flooring, which may either be sized or not before its application. The floor may be subsequently varnished; or waxed with pal-affine, or like wax. If not so varnished, the stain itself will render the flooring very slowly combustible; as it will also do when applied to.

roofs or wooden erections. If this stainis laid on paper felting, which absorbs it rapidly, it is also practically non-inflammable, besides acquiring sanitary powers. The stain may be laid on blocks of ordinary woods used in parquetry, either veneered or of the solid kind. I find certain portions of the bark, if previously thoroughly dried, can be used as solid blocks forpavement with a veryslight alkaline treatment, such as is already specified. liquor thus extracted gives the block a beantiful polish just as if the manufactu red liquor had been applied to it. But, further, the color of the blocks may be deepened or variedjust as successive coats of the red liquor are added, or anyothercolor to which the liquormay have been changed by suitable chemical ingredients, or by usin gihe original pine c'olor extracted from sequoia wood. The bark or wood may be similarly treated for use in marquetry. The wood itself, when used in larger bulk, may be deepened in color, by the application of the stain from the bark, so as to rival sat-.

inwood. A filler, preferably made of chalk and sulphate of alumina with this red liquor as hereinafter specified, may be previously added. The red or brown liquor obtained as above specified, when mixed in proper proportions with ground shale, or similar absorptive material, containing carbon and iron and sulphate of alumina, forms a filtering m edium which clears the dirty effluent waters, such as are discharged by paper-mills, oilworks, and similar factories. I use it after the method of ordinary filters. The red or brown liquor obtained may be used as a pigment by making a lake with sulphate of alumina and carbonate oflime. Thus,two pounds chalk and four pounds soda liquor, and four pounds sulphate of alumina mixed together in a stirring mill, then dried and powdered, forms a non-inflammable paint, useful in places where the liquor alone cannot be applied. When selenite or sulphate of lime is added in proper proportions, a handy cement is formed useful in ships, and other like places, subject to sudden fires. The red liquor, or the dried concentrated paste to be afterward specified, may be used by color-makers mixed with ground mineral earth; for example, barium sulphate, whiting, barytes and other similar ingredients. In order to fix the .Vandyke brown color, a small portion of the sulphate of iron or copper, or a like salt, may be added. The red liquor when used after the ordinary methods of the tanner, gives the leather the characteristic red color. When mixed with on e-fourth of boracic acid, ora variable proportion to suit the taste of the user, a leather stain is given suitable for leggins, boots or shoes. The liquor obtained from the wood may be so treated by suitable admixture, as to give a lighter leather dye than that from the bark. I find that either liquor is a suitable ingredient for leather dye, or stain.

The liquid solution, heretofore described from either the wood or bark, may be made into a solid paste, by evaporating itdown in a shallow vessel subjected to a heat of 125 Fahrenheit, or so. The solid thus formed, is soluble in hot water and may be used for any of the purposes above described.

In preparing this extract for the wool-dyer who may use it with a bichrome mordant or for special pigments soluble in oil or spirits, and before evaporating it down to a paste, I saturate it with carbonic acid gas, so as to convert the free alkali into carbonate or bicarbonate.

When dilute sulphuric, or hydrochloric acid is added to the liquid solution already specified, in the proportions of from five to ten per cent, or more, a precipitate of phlobaphenes and the like, is formed. I find this to be soluble in methylated spirit, yielding wood-stains of alighter color than those previously specified.

My invention is not limited to the exact methods or processes of treating the wood and bark herein described, as these may be varied, or modified'without departing from my invention. For instance, I may allow a certain amount of the original color to remain and extract only so much as is deemed expedient by the method as above described; in this Way the residual wood and bark would not be destroyed, and might afterward be used for other purposes.

1 am aware that vegetable extracts have been obtained from other barks, such as oak or hemlock by heating in water and an alkali. Tannin may be obtained from these by merely dissolving in ater, though more thoroughly Lilh alkalies. I have discovered that the bark and wood of the redwood will not yield extracts by mere steeping in water, or by such likeiprocesses as aroused by tanners in ordinarily obtaining extracts from bark. With redwood it is absolutely necessary to use alkalies. This necessityinvolves and renders essential a further step, namely, the neutralizing of the alkalies in the liquor before the extracts are reduced to merchantable form. Without this step the dyes thus obtained from redwood are unmerchantable, rotting the wool. This neutralizing of the alkalies may be effected by any suitable means.

I have hereiubefore mentioned carbonic acid and hydrochloric or sulphuric acid in this connection; and I have also mentioned the more complete precipitation by paraffi no oil or petroleum and when the alkaline liquor is thus treated, the solid matters afterward obtained, are valuable products retaining the color and capable of competing with fustic.

Having thus desc ibed my invention, What I claim as new, and desire to secure by Let ters Patent, is

,, s In .1

The improvement in the process of obtain- In witness whereof I have hereunto set my ing vegetable products from the bark and hand. wood of the redwood tree (Sequoia semperm'rens) which consists first in comminuting 5 the bark and wood; second, in heating in wa- Witnesses:

ter and a caustic alkali or carbonate of an JOHN M. BELL, alkali; third, in neutraliz ng the 31k ali in 137 Princes Street, Edinburgh, Writer 250 the the liquorthus obtained; and fourth, obtain- Signet. ing the solid matters from said neutralized J. G. ORUICKSHANK,

1o liquor, substantially as herein described. 137 Princes Street, Edinburgh.

ANDREW TAYLOR. 

